On Nov. 12, 2008, EPA substantially strengthened the National Ambient Air Quality Standards for lead (see 73 FR 66964). EPA lowered the level of the primary (health-based) standard from 1.5 micrograms per cubic meter (µg/m3) to 0.15 µg/m3, measured as total suspended particles. EPA also revised the secondary (welfare-based) standard to be identical to the primary standard.

The standard is based on the highest rolling three-month average over a period of three years and two months. The standard is met at a monitoring site when the three month average is less than or equal to 0.15 μg/m3. For specific rules and technical information, consult 40 CFR Pt. 50, Appendix R.

Disclaimer: The following data is calculated using the lead National Ambient Air Quality Standards regulations. data shown below has been subject to data review and validation procedures by the department. The units for all averages in this table are micrograms per cubic meter. Data in this table, is calculated at local conditions using daily average temperature and barometric pressure. Lead is sampled on a set schedule. Results in this table are a combination of samples for this site taken on an every sixth day run schedule.

The units for all averages in this chart are micrograms per cubic meter.

Doe Run Post office Sampler

Year

Month

Monthly Average

3-Month Rolling Average

Month

Monthly Average

3-Month Rolling Average

2010

January

0.052

0.067

July

February

0.022

0.065

August

March

0.012

0.029

September

April

October

May

November

June

December

2009

January

0.041

July

0.022

February

0.029

August

0.033

March

0.031

September

0.025

April

0.026

October

0.023

May

0.026

November

0.022

June

0.019

December

0.021

Disclaimer: The following table is a summary of Lead data (through 2008) calculated using the previous Lead National Ambient Air Quality Standards regulations, which compares a quarterly average to1.5 μg/m3. Data was calculated using EPA standard conditions of ambient temperature and barometric pressure. All data in this table is historical and will not be updated.

The units for all averages in this chart are micrograms per
cubic meter.

On Nov. 12, 2008, EPA substantially strengthened the National Ambient Air Quality Standards for lead (see 73 FR 66964). EPA lowered the level of the primary (health-based) standard from 1.5 micrograms per cubic meter (µg/m3) to 0.15 µg/m3, measured as total suspended particles. EPA also revised the secondary (welfare-based) standard to be identical to the primary standard.

The standard is based on the highest rolling three-month average over a period of three years and two months. The standard is met at a monitoring site when the three month average is less than or equal to 0.15 μg/m3. For specific rules and technical information, consult 40 CFR Pt. 50, Appendix R.

Disclaimer: The following data is calculated using the lead National Ambient Air Quality Standards regulations. data shown below has been subject to data review and validation procedures by the department. The units for all averages in this table are micrograms per cubic meter. Data in this table, is calculated at local conditions using daily average temperature and barometric pressure. Lead is sampled on a set schedule. Results in this table are a combination of samples for this site taken on an every sixth day run schedule.

The units for all averages in this chart are micrograms per cubic meter.

Doe Run Glover Big Creek Sampler

Year

Month

Monthly Average

3-Month Rolling Average

Month

Monthly Average

3-Month Rolling Average

2010

January

0.030

0.026

July

February

0.033

0.030

August

March

0.018

0.027

September

April

October

May

November

June

December

2009

January

0.045

July

0.028

February

0.039

August

0.044

March

0.052

September

0.032

April

0.049

October

0.017

May

0.040

November

0.019

June

0.019

December

0.052

Disclaimer: The following table is a summary of Lead data (through 2008) calculated using the previous Lead National Ambient Air Quality Standards regulations, which compares a quarterly average to1.5 μg/m3. Data was calculated using EPA standard conditions of ambient temperature and barometric pressure. All data in this table is historical and will not be updated.

The units for all averages in this chart are micrograms per
cubic meter.